Iran needs to make best use of its conditions:
1: It is not a nuclear power and will only be a latent one in future (see Japan)
2: All other powers able to build a ICBM are nuclear powers (except Japan)
3: War drums from the Trump administration and cancellation of Barjam/JCPOA
A indefensible global strike capability is a central element to being a world military power.
If done in the right way, Iran could attend a status in which it would have such a capability in a legal way.
First: Irans BM arsenal is so large because it can use them in warfare.
As a non-nuclear power there is no risk of them being tipped with nuclear warheads that would require a nuclear counter attack.
Hence it is essential that Iran remains non-nuclear and at most a latent nuclear power if it wants to use its arsenal.
In practice, the capability this would offer in any kind of a limited conflict would be even higher than e.g the B-2 fleet of the USAF that is and was a important enabler for military intervention.
World powers have such assets such as submarine launched LACM and aircrafts carriers and none of those is as lethal (indefensible) as a conventional ICBM capability.
So we learn that such a capability would be in line with Sardar Salamis statement and what we see via IMINT and intelligence reports.
It must also be understood that such a capability could not be used if Iran would be a nuclear power, at least not without receiving a nuclear counter reaction by nuclear powers that feel threatened (no risk can be accepted in this case).
A global strike capability via a conventional ICBM would be a world first and cause worldwide opposition, but the Trump admin could provide a justification, more so because Iran is already de facto under a international embargo.
Once this capability is attained AND legitimized, it would be a unique capability worldwide. Upgraded with a hypersonic glide vehicle, it could stay the most effective weapon for Iran until the end of the century.
For the Europeans (and Russians and Chinese), Iran could agree to an INF-like limitation of IRBMs: Only MRBMs against regional threats and ICBMs against the U.S.
We have an idea on which the Shahround solid fuel team is working on: a 40-50ton ICBM (excluding a larger SLV). This could have a payload of 1.5 tons and more, depending on technology.
That would be three 500kg warheads.
If we now upscale the cost calculation and assume a Sejil costs $400k, one such ICBM could end up costing 1,5 mio USD. This translates to $500k for a 500kg high velocity payload delivered to intercontinental range.
If this is not feasible cost wise: Shahid Tehrani Moghaddams final project was for something even larger.
Something that would probably be able to deliver a payload of more than 3 tons.
Together with a Saman based PBV, this would result in at least 6 such 500kg warheads. Here the cost calculation could pay-off.
However such a heavy ICBM would be static, only for silos or mountain bases.
The enemy would be paralyzed by strikes it can't defend against and which it the highest value objects of the country with pin-point precision.
A limited defense would be certainly possible but the numbers Iran would throw, would make it a hopeless endeavor.
Yes would make sense if the Nuclear Powers who have those weapons today were logical actors that would only retaliate with Nukes if ever attacked with Nukes!
Now what if Iran is attack and Iran responds with conventional missiles and yet the retaliation to Iran's response is a nuclear attack? What then?
I'm not saying nukes are a necessity for Iran but worst case and at the very least we need to have the equipment ready at a safe location to build them in a very short timespan so if ever a single nuke drops on Iran we can retaliate in kind in under a week so it never happens again!
Also if the U.S. continues to equip the Saudi's with nuclear tech that will lead to a Saudi Nuke then we really don't have a choice because Iran simply can't afford to be a none nuclear state that's surrounded by nuclear powers from every side
I also think mutually assured destruction is a far more prudent and proven tactic!
The major nuclear powers of the world have air dropped nuclear bombs, cruise missiles armed with nukes, torpedo nukes, Air to Air nukes, nuclear artillery,..... & nuclear powered BM's so if ever U.S. fires cruise missiles at us or deploys bombers against us we wouldn't know if they have nukes on them or not until they hit so why should Iranian BM be any different?
And I believe the argument that no one would use a none nuclear ICBM were for the day's the accuracy to take out targets with high accuracy didn't exist and that argument will continue to fade as the tech to make the projectiles smaller and more accurate
If for example a $10 Million USD Iranian ICBM armed with decoys and 10 highly accurate MIRV with a CEP of 10 meters and ability to take out 10 fortified aircraft bunkers up to 10,000km away I'd say that's well worth the cost
same with a larger diameter $40 Million USD missile carrying 40 conventional MIRV even it it's for targets within 3,000km I would still say it would be well worth it without nukes as long as you have the accuracy to allow you to use larger number of lighter projectiles to take out bunkers and yes compared to a nuke the structural damage and death toll may not be so significant but for Iran the real prize is the military assets not the death toll or structural damage
